Lathes and similar machine tools typically are provided with a controllably movable cross slide, to which cutting tools are mounted. Even though the cross slide may be movable both transversely and longitudinally during cutting operations, it is nevertheless important in many cases to be able to mount the cutting tool to the cross slide with a substantial degree of precision.
Quite typically, adjustment of tool holders on the cutting machine cross slide is accomplished by slightly loosening the clamping bolt or bolts and tapping the tool or tool holder with a hammer. However, this is difficult and time consuming, and precision adjustment is achieved, if at all, only with considerable effort.
It is known, of course, to provide tool holders with precision adjustment features. However, insofar as we are aware, the known devices for this purpose tend to be complex and expensive and, at the same time, less than fully effective.
In accordance with the present invention, a novel and greatly simplified form of precision adjustable tool holder is provided, which is both highly efficient and reliable in operation and, at the same time, is relatively simple in construction.
In accordance with one aspect of the invention, a precision adjustable tool holder is provided in which the unit as a whole is secured to the cross slide of the machine tool by a pair of through-bolts, one of which secures a normally fixed base block and the other of which secures not only the base block but the adjustable tool holding block as well. The through-bolts extend through to an elongated clamping bar, which is received in a Tee slot in the machine cross slide. This construction enables a base block member to be fixed to the cross slide in an approximate position, while accommodating precision, micrometer adjustment of the tool holding block itself. When the tool holding block is properly positioned, the through-bolt extending through it is tightened, which not only fixes the position of the tool block, but also secures it tightly to the elongated clamping bar and thus directly secures it to the cross slide.
In a first modified version of the new tool holder, a pair of adjustably movable tool holding blocks are mounted on a single base block. Each of the tool holding blocks is separately precision adjustable, after which each of the adjustable blocks is clamped tightly, through the base block, to the elongated clamping bar. This arrangement accommodates a high degree of precision in the simultaneous cutting of, for example, a flange, where the respective tools are simultaneously cut on front and back surfaces.
In a second modified version of the new tool holder, the clamping bar is constructed in a manner such that it serves both as a clamping bar and as a base block, enabling some simplification of the structure and a reduction in manufacturing cost.
For a better understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of a preferred embodiment, and to the accompanying drawing.